Method for spray tank cleanout

ABSTRACT

A method for spray tank cleanout. In particular, the invention further relates to a method for reducing residual sulfonylurea pesticide contamination of a spray tank from which the sulfonylurea is applied, and a composition for achieving this method.

CROSS-REFERENCE TO RELATED APPLICATIONS

This U.S. patent application is a continuation of U.S. patentapplication Ser. No. 14/381,348, filed Aug. 27, 2014, which is anational phase entry of PCT/CN2013/073222, filed 26 Mar. 2013, whichclaims benefit of GB 1207097.5, filed 20 Apr. 2012, the entire contentsof which are incorporated herein by reference for all purposes.

BACKGROUND

Field

This present disclosure provides a method for spray tank cleanout. Inparticular, the disclosure further relates to a method for reducingresidual sulfonylurea pesticide contamination of a spray tank from whichthe sulfonylurea is applied.

Related Art

Sulfonylureas, as a class, are highly active pesticides. For thisreason, it is desirable to clean out spray equipment before theequipment is subsequently used to treat crops sensitive to thesulfonamide herbicide used in the previous application. Adequatecleanout may require a rinsing procedure that is time-consuming andresults in wastewater requiring proper environmental disposal.Furthermore, cleanout can be affected if the spray equipment containsorganic deposits remaining from previous crop protection chemicalapplications or from other chemicals tank-mixed with the sulfonamideherbicide composition.

PCT patent application publication WO93/16596 describes a method forreducing residual sulfonylurea herbicide contamination of sprayequipment by requiring as the first step the formulation of thesulfonylurea active ingredient in the form of an agriculturally suitablewater soluble salt. The method for reducing residual sulfonylureapesticide contamination of a spray tank from which the sulfonylurea isapplied, comprising the steps: i) formulating the sulfonylurea thesteps: agriculturally suitable water soluble salt composition beforespray tank application, thereby increasing solubility of thesulfonylurea and decreasing the amount of insoluble sulfonylureaavailable for residual contamination of the spray tank; ii) applying thesulfonylurea salt composition to the crop while minimizing buildup ofinsoluble sulfonylurea in the spray tank; and (iii) rinsing the spraytank substantially free of residual sulfonylurea, after application, inan operation in which the sulfonylurea remaining in the spray tank isreduced significantly versus the amount remaining when sulfonylurea isnot formulated as a water-soluble salt before application. But thismethod has disadvantages. In the tank cleanout protocol I, step 4, step5, step 6, and step 7 all mentioned a cleaning solution. The cleaningsolution can be water, or an ammonium hydroxide, or sodium hypochloritesolution. Especially in step 7, ammonium hydroxide solution was used. Soeven using sulfonylurea water soluble salt in the composition, washingthe spray equipment with the cleaning solution was also necessary afterfinishing spraying.

SUMMARY

The present disclosure provided a composition with sulfonylurea whichhas improved spray equipment clean-out properties and reduces residualsulfonylurea herbicide contamination of spray equipment. There is noneed for using a cleaning solution to wash the spray equipment afterapplication. Simple washing with fresh water after application isenough. This facilitates the farmers' washing step and saves time.

An embodiment of the invention relates to a composition comprising:

(i) from 2% to 90% by weight sulfonylurea water soluble salt;

(ii) from 1% to 50% by weight ethanolamine;

(iii) from 0-95% of one or more additional formulating ingredients;

the sum of the weight percents of all the ingredients in the compositiontotaling 100%.

An embodiment of the invention further relates to a method for reducingresidual sulfonylurea pesticide contamination of a spray tank from whichthe sulfonylurea is applied, comprising the steps:

(a) formulating the sulfonylurea as an agriculturally suitable watersoluble salt;

(b) preparing a composition comprising by weight:

(i) from 2% to 90% sulfonylurea water soluble salt;

(ii) from 1% to 50% ethanolamine;

(iii) from 0-95% of one or more additional formulating ingredients;

the sum of the weight percents of all the ingredients in the compositiontotaling 100%;

(c) applying the sulfonylurea salt composition to the crop whileminimizing buildup of insoluble sulfonylurea in the spray tank, and

(d) rinsing the spray tank substantially free of residual sulfonylurea,after application.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

It has been discovered that the sulfonylureas herbicide compositionaccording to an embodiment of the invention has improved spray equipmentclean-out properties and reduces residual sulfonylurea herbicidecontamination of spray equipment. In addition, there is no need forusing a cleaning solution to wash the spray equipment after application.Simple washing with fresh water after application is enough. Thisfacilitates the farmers' washing step and saves time.

The sulfonylureas whose spray tank buildup is curtailed by the method ofan embodiment of this invention are the sulfonylurea acids either whenused alone or with one or more tank mix partners. The benefits achievedby this invention have been found to be more pronounced when thesulfonylurea is employed with a tank mix partner.

The benefits are even more noteworthy when earlier tank mixes have leftorganic deposits on inside spray tank surfaces. In such instances, it isbelieved that undissolved particles of the sulfonylurea are held by theorganic deposit and kept from becoming resuspended or dissolved in thespray tank water. Thereafter, should the spray tank be employed on acrop sensitive to the sulfonylurea, damage may result either frommigration into the tank water of particles formerly trapped by theorganic deposit or by actual sloughing off of the organic depositcarrying embedded sulfonylurea particles with it.

The problem of difficult spray tank cleanout is exacerbated bysulfonylureas used at relatively high concentrates. Since watersolubility of the sulfonylurea active ingredient in its acid form is solow, tank mixes of the sulfonylureas are primarily suspensions.Suspended particles can collect on tank walls, in tubing, or be trappedby organic deposits that may be present inside the tank. If a later tankmix sends the sulfonylurea into solution or suspension, sensitive cropscan be damaged.

This problem is avoided partly by employing sulfonylureas in awater-soluble salt form. The sulfonylurea salt form shows a fasterdissolution rate than the corresponding sulfonylurea acid. In order toavoid this problem completely, a washing with the clean solution isnecessary after application.

The invention, in an embodiment, provides a composition comprising byweight:

(i) from 2% to 90% sulfonylurea water soluble salt;

(ii) from 1% to 50% ethanolamine;

(iii) from 0-95% of one or more additional formulating ingredients; thesum of all the ingredients in the composition totaling 100%.

The invention, in an embodiment, further provides a method for reducingresidual sulfonylurea pesticide contamination of a spray tank from whichthe sulfonylurea is applied, comprising the steps:

(a) formulating the sulfonylurea as an agriculturally suitable watersoluble salt;

(b) preparing a composition comprising by weight:

(i) from 2% to 90% sulfonylurea water soluble salt;

(ii) from 1% to 50% ethanolamine;

(iii) from 0-95% of one or more additional formulating ingredients; thesum of all the ingredients in the composition totaling 100%;

(c) applying the sulfonylurea salt composition to the crop whileminimizing buildup of insoluble sulfonylurea in the spray tank, and

(d) rinsing the spray tank substantially free of residual sulfonylureaafter application.

The composition of the present invention has improved spray equipmentclean-out properties and reduces residual sulfonylurea herbicidecontamination of spray equipment. In addition, there is no need forusing a cleaning solution to wash after application. Simple washing withfresh water after application is enough. This facilitates the farmers'washing step and saves time.

The sulfonylureas for use in the invention include:

-   2-chloro-N[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]benzenesulfonamide    (chlorsulfuron);-   Methyl    2-[[[[(4,6-dimethyl-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]    benzoate (sulfometuron-methyl);-   Ethyl    2-[[[[[4-chloro-6-methoxy-2-pyrimidinyl]amino]carbonyl]amino]sulfonyl]    benzoate (chlorimuron ethyl);-   Methyl 2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl) amino]    carbonyl] amino] sulfonyl]benzoate (metsulfuron-methyl);-   Methyl    2-[[[[[4,6-dimethoxy-2-pyrimidinyl]amino]carbonyl]amino]sulfonyl]-6    (trifluoromethyl)-3-pyridine-carboxylate (flupyrsulfuron-methyl);-   Methyl    2-[[[[[4-ethoxy-6-(methylamino)-1,3,5-triazin-2-yl]amino]carbonyl]amino]sulfonyl]    benzoate (ethametsulfuron-methyl);-   2-(2-chloroethyloxy)-N-[    [(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]-benzenesulfonamide;-   Ethyl    5-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-1-methyl-1H-pyrazole-4-carboxylate    (pyrazosulfuron-ethyl);-   N-[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]-3-(ethylsulfonyl)-2-pyridinesulfonamide    (rimsulfuron);-   Methyl    3-[[[[(4-methoxy-6-methyl-1,3,5-triazine-2-yl)amino]carbonyl]amino]sulfonyl]-2-thiophenecarboxylate    (thifensulfuron-methyl);-   Methyl    2-[[[[N-(4-methoxy-6-methyl-1,3,5-triazine-2-yl)N-methylamino]carbonyl]amino]sulfonyl]benzoate    (tribenuron-methyl);-   Methyl 2-[[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl] amino]    sulfonyl]methyl]benzoate (bensulfuron methyl);-   2-[[[[[4,6-bis(difluoro methoxy)-2-pyrimidinyl] amino]    carbonyl]amino]sulfonyl]benzoate;-   2-[[[[(4,6-dimethoxy-2-pyrimidiny)amino]carbonyl]amino]sulfonyl]N,N-dimethyl-3-pyridinecarboxamide    (nicosulfuron);-   Methyl    2-[[[[[[4-dimethylamino]-6-(2,2,2-trifluoroethyoxy)-1,3,5-triazin-2-yl]amino]carbonyl]    amino]sulfonyl]-3-methylbenzoate; and-   N-[[(4,6-dimethyl-2-pyrimidinyl)amino]carbonyl]-1-methyl-4-(2-methyl-2H-tetrazol-5-yl)-1H-pyrazole-5-sulfonamide    (azimsulfuron).

More preferred sulfonylurea compounds are:

-   Methyl    3-[[[[(4-methoxy-6-methyl-1,3,5-triazine-2-yl)amino]carbonyl]amino]sulfonyl]-2-thiophenecarboxylate    (thifensulfuron-methyl);-   Methyl    2-[[[[(4,6-dimethyl-2-pyrimidinypamino]carbonyl]amino]sulfonyl]benzoate    (sulfometuron-methyl);-   Methyl 2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)    amino]carbonyl]amino]sulfonyl]benzoate (metsulfuron-methyl);-   Ethyl 5-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]    sulfonyl]-1-methyl-1H-pyrazole-4-carboxylate (pyrazosulfuron-ethyl);-   N-[    [(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]-3-(ethylsulfonyl)-2-pyridinesulfonamide    (rimsulfuron);-   Methyl    2-[[N-(4-methoxy-6-methyl-1,3,5-triazine-2-yl)-N-methylamino]carbonyl]amino]sulfonyl]benzoate    (tribenuron-methyl);-   2-[[[[(4,6-dimethoxy-2-pyrimidiny)amino]carbonyl]amino]sulfonyl]N,N-dimethyl-3-pyridinecarboxamide    (nicosulfuron);

2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]benzenesulfonamide (chlorsulfuron)

Salts of the sulfonylureas are generally known as are methods for makingthem. Preferred salt cations are the sodium, potassium, calcium,magnesium, ammonium and alkylammonium cations. Preferred sulfonylureasalts are the sodium and calcium salts of tribenuron methyl; thepotassium salt of thifensulfuron methyl; the ammonium salt ofchlorsulfuron and the potassium salt of metsulfuron methyl.

In the composition of an embodiment of the invention, the amount ofethanolamine present may present depend upon the concentrate of thesulfonylurea water soluble salt active ingredient and may be determinedby routine experimentation. The ethanolamine is preferably present in anamount such as to give a weight ratio of the sulfonylurea water solublesalt to the ethanolamine of from 1:90 to 90:1.

The composition of embodiments of the present invention may be providedin the form of liquid or solid. Use formulations include dusts,granules, pellets, solutions, suspensions, emulsions, gels, actives inplastic, wettable powders, emulsion concentrates, dry flowables and thelike, consistent with the physical properties of the active ingredient,mode of application and environmental factors such as soil type,moisture and temperature. Sprayable formulations can be extended insuitable media and used at spray volumes from about one to severalhundred liters per hectare. High strength compositions are primarilyused as intermediates for further formulation.

The composition of embodiments of the present invention can contain oneor more additional formulating ingredients in a total amount by weightof 0 to 95%. Additional formulating ingredients can include liquiddiluents, solid diluents, wetting agents, dispersants, emulsifiers,chemical stabilizers and other formulation ingredients.

Liquid diluents include, for example water, N,N-dimethylamide, dimethylsulfoxide, N-alkylpyrrolidone, ethylene glycol, polypropylene glycol,propylene carbonate, dibasic esters, paraffines, alkylbenzenes, alkylnaphthalenes, glycerine, triacetine, oils of olive, castor, linseed,sesame, corn, peanut, cotton-seed, soybean, rape-seed and coconut,ketones such as cyclohexanone, 2-heptanone, isophorone and4-hydroxy-4-methyl-2-pentanone, acetates such as hexyl acetate, heptylacetate and octyl acetate, and alcohols such methanol, cyclohexanol,decanol, benzyl and tetrahydrofurfuryl alcohol.

Solid diluents can be water-soluble or water-insoluble. Water-solublesolid diluents include salts such as alkali metal phosphates (e.g.,sodium dihydrogen phosphate), alkaline earth phosphates, sulfates ofsodium, potassium, magnesium and zinc, sodium and potassium chloride,and sodium benzoate and sugars and sugar derivatives such as sorbitol,lactose and sucrose. Examples of water-insoluble solid diluents include,but are not limited to clays, synthetic and diatomaceous silicas,calcium and magnesium silicates, titanium dioxide, aluminum, calcium andzinc oxide, calcium and magnesium carbonate, calcium and barium sulfate,and charcoal.

The emulsifiers can be cationic, anionic or nonionic, but are moretypically anionic or nonionic. Examples of particularly suitable anionicsurfactants for this purpose are sulfonates such as calcium dodecylbenzesulfonate. Examples of particularly suitable nonionic surfactantsare polyoxyethylated (POE) sorbitan esters such as POE(20) sorbitantrioleate and polyoxyethylated (POE) sorbitol esters such as POE(40)sorbitol hexaoleate. POE(20) sorbitan trioleate is commerciallyavailable under the tradenames ATLAS G1086 and CIRRASOL G1086 marketedby UniqEMA. Combination of a POE sorbitan ester with a POE sorbitolester allows optimizing the HLB (hydrophiliclipophilic balance) value ofthe surfactant to obtain the highest quality emulsion (smallestsuspended droplets) when the composition is added to water. High qualityof emulsions typically leads to optimal herbicidal performance.

Wetting agents include but are not limited to alkyl sulfosuccinates,laureates, alkyl sulfate and phosphate esters, acetylenic diols,ethoxyfluorinated alcohols, ethoxylated silicones, alkyl phenolethoxylates, benzene sulfonates, alkyl-substituted benzene sulfonates,alkyl α-olefin sulfonates, naphthalene sulfonates, alkyl-substitutednaphthalene sulfonates, condensates of naphthalene sulfonates andalkyl-substituted naphthalene sulfonates with formaldehyde, and alcoholethoxylates. Of note are compositions comprising up to 10% by weight ofwetting agent.

Dispersants include, but are not limited to, sodium, calcium andammonium salts of ligninsulfonates (optionally polyethoxylated); sodiumand ammonium salts of maleic anhydride copolymers; sodium salts ofcondensed phenolsulfonic acid; and naphthalene sulfonate-formaldehydecondensates. Of note are compositions comprising up to 10% by weight ofdispersant. Ligninsulfonates, such as sodium ligninsulfonates, areparticularly useful for the composition of embodiments of the invention.

Chemical stabilizers prevent decomposition of active ingredient duringstorage. Inorganic bases such as lithium, sodium and potassiumphosphates can help prevent decomposition of active ingredient. Chemicalstabilizers include, but are not limited to lithium, sodium, andpotassium phosphates, sodium dihydrogen phosphate, sulfates of alkalineearth metals and transition metals such as magnesium, zinc, aluminum andiron; calcium chloride and oxide; and boric anhydride. Of note arecompositions comprising up to 10% by weight of chemical stabilizer.

Other formulation ingredients can be used in embodiments of the presentinvention, such as dyes, defoamers, drying agents, and the like. Theseingredients are known to one skilled in the art.

Solutions are prepared by simply mixing the ingredients. Fine solidcompositions are made by blending and, usually, grinding as in a hammermill or fluid energy mill. Water-dispersible granules can be produced byagglomerating a fine powder composition; suspensions are prepared bywet-milling; granules and pellets can be made by spraying the activeingredient upon preformed granular carriers or by agglomerationtechniques. Pellets can be prepared as described in U.S. Pat. No.4,172,714. Water-dispersible and water-soluble granules can also beprepared as taught in DE3246493.

Sulfonylurea salts of this invention can be used alone or in combinationwith other commercial herbicides (including other sulfonylureas orsulfonylurea salts), insecticides, or fungicides. Mixtures containingsulfonylurea and other commercial herbicides, insecticides, orfungicides with ethanolamine are particularly useful in minimizing spraytank cleanout when compared to the same mixture without ethanolamine.

In the following examples, all percentages are by weight and allformulations are worked up in conventional ways.

PREPARATION EXAMPLES Examples Example 1

Thifensulfuon methyl potassium salt 1% Ethanolamine 90%  Sorbitantrioleate (Uniqema Tween 85) 5% Calcium dodecyl benzesulfonate (Clariant70B) 3% Water balance to 100%

Example 2 High Strength Concentrate

Metsulfuron-methyl sodium salt  90% Ethanolamine   1% Silica aerogel0.5% Synthetic amorphous fine silica balance to 100%

Example 3 Wettable Power

Pyrazosulfuron-ethyl sodium salt 20% Ethanolamine 10% Sodium alkylnaphthalenesulfoate (Morwet EFW,  3% Akzo Nobel) Sodium ligninsulfonates(Polyfon H, Westvaco)  3% Clay balance to 100%

Example 4 Water Dispersible Granule

Tribenuron methyl sodium salt 75% Ethanolamine 15% Sodium alkylnaphthalenesulfoate (Morwet EFW,  2% Akzo Nobel) Sodium ligninsulfonate(Polyfon H, Westvaco)  3% Clay balance to 100%

Example 5 Suspensions

Mesosulfuron methyl calcium salt 20%  Ethanolamine 20%  Sodiumligninsulfonate (Polyfon H, Westvaco) 5% Sorbitan trioleate (UniqemaTween 85) 5% PG 5% Water balance to 100%

Example 6 Soluble Granules

Metsulfuron methyl potassium salt 50% Ethanolamine 30% Sodium alkylnaphthalenesulfoate (Morwet EFW,  2% Akzo Nobel) Sodium ligninsulfonate(Polyfon H, Westvaco)  3% Sucrose balance to 100%

Example 7 Soluble Powder

Chlorsulfuron ammonium salt  5% Ethanolamine 15% Sodium alkylnaphthalenesulfoate  2% (Morwet EFW, Akzo Nobel) Sodium ligninsulfonate 3% (Polyfon H, Westvaco) Sucrose balance to 100%

Example 8 Solutions

Rimsulfuron sodium salt  2% Ethanolamine 80% Sorbitan trioleate (UniqemaTween 85)  5% Calcium dodecyl benzesulfonate (Clariant 70B)  3% Waterbalance to 100%

Example 9 Suspensions

Trifluoxyfluron calcium salt  4% Ethanolamine 80% Sodium ligninsulfonate(Polyfon H, Westvaco)  5% Sorbitan trioleate (Uniqema Tween 85)  5% PG 5% Water balance to 100%

Example 10 Water Dispersible Granule

Sulfometuron methyl magnesium salt 40% Ethanolamine  2% Sodium alkylnaphthalenesulfoate  2% (Morwet EFW, Akzo Nobel) Sodium ligninsulfonate 3% (Polyfon H, Westvaco) Clay balance to 100%

Example 11 Granules

Bensulfuron-methyl ammonium salt 10% Ethanolamine 20% Attapulgitegranules balance to 100%

Example 12 Wettable Powders

Nicosulfuron calcium salt 75% Ethanolamine 15% Sodium alkylnaphthalenesulfoate  3% (Morwet EFW, Akzo Nobel) Sodium ligninsulfonate 3% (Polyfon H, Westvaco) Clay balance to 100%

Example 13 Solutions

Triflusulfuron-methyl sodium salt 15% Ethanolamine 50% Sorbitantrioleate (Uniqema Tween 85)  5% Calcium dodecyl benzesulfonate(Clariant 70B)  3% N-methylpyrrolidone balance to 100%

Example 14 Solutions

Chlorsulfuron ammonium salt  2% Ethanolamine 60% Sorbitan trioleate(Uniqema Tween 85)  5% Calcium dodecyl benzesulfonate (Clariant 70B)  3%Water balance to 100%

Example 15 Soluble Powders

Ethamesulfuron-methyl sodium salt 60% Ethanolamine  2% Sodium alkylnaphthalenesulfoate  2% (Morwet EFW, Akzo Nobel) Sodium ligninsulfonate 3% (Polyfon H, Westvaco) Sucrose balance to 100%

Example 16 Soluble Granules

Azimsulfuron potassium salt 50% Ethanolamine  1% Sodium alkylnaphthalenesulfoate  2% (Morwet EFW, Akzo Nobel) Sodium ligninsulfonate 3% (Polyfon H, Westvaco) Sucrose balance to 100%

Example 17 Suspensions

Chlorimuron-ethyl calcium salt  1% Ethanolamine 50% Sodiumligninsulfonate (Polyfon H,  5% Westvaco) Sorbitan trioleate (UniqemaTween 85)  5% PG  5% Water balance to 100%

Example 18 Soluble Granules

Flupyrsulfuron-methyl sodium salt 50% Ethanolamine  5% Sodium alkylnaphthalenesulfoate  2% Sodium ligninsulfonate (Polyfon H, Westvaco)  3%Sucrose balance to 100%

Example 19 Suspensions

Flupyrsulfuron-methyl calcium salt  5% Ethanolamine 50% Sodiumligninsulfonate (Polyfon H, Westvaco)  5% Sorbitan trioleate (UniqemaTween 85)  5% PG  5% Water balance to 100%

Comparative Examples

In Comparative examples A-S without using Ethanolamine, the otheringredients are the same as with the corresponding Examples 1-19, andethanolamine was replaced using diluents in the composition.

The compositions were evaluated by the following clean-out testprocedure that determines the sulfonamide herbicide residue that couldpotentially remain in organic deposits in a spray tank.

Tank Cleanout Protocol I

(Sulfonylurea Plus Tank Mix Partner)

Step 1

Add water to the tank and when half-filled, add a sample from Example1-19 and Comparative example A-S in each separate tank with agitation.Fill tank to the 90% level with water. Agitate the tank for a minimum of5 to 10 minutes.

Step 2

Spray the tank contents through the boom. Drain any remainder from thetank.

Step 3

Rinse the interior tank surfaces with water; use about 10% of the tankcapacity. Spray this rinse through the boom. Drain the remainder fromthe tank.

Step 4

Remove all nozzles, nozzle screens, in-line filters, or filters of anytype and clean thoroughly in a bucket of water. Remove any residues ordeposits using a brush.

Step 5

Fill tank half full with fresh water. Sample water wash in tank (sampleused for bioassay test). Spray 10 to 20 gallons through the boom andthen the sample at a nozzle (sample used for bioassay test). Drain theremainder of the contents. Remark: In whole cleaning process, only freshwater was used. Additional cleaning solution or ammonium hydroxide isnot used.

TABLE I Initial Sulfonylurea concentration in the Percent tank mixinjury Examples Sulfonylurea (ppm) Tank mix partner 1 Example 1Thifensulfuon methyl 400 2,4-D 0 potassium salt ComparativeThifensulfuon methyl 400 2,4-D 50 example A potassium salt Example 2Metsulfuron-methyl 500 Propiconazole 0 sodium salt ComparativeMetsulfuron-methyl 500 propiconazole 90 example B sodium salt Example 3Pyrazosulfuron-ethyl 750 Flutriafol 0 sodium salt ComparativeMetsulfuron methyl 750 Flutriafol 20 example C sodium salt Example 4Tribenuron methyl 600 2,4-D 0 sodium salt Comparative Tribenuron methyl600 2,4-D 40 example D sodium salt Example 5 Mesosulfuron methyl 775propiconazole 0 calcium salt Comparative Tribenuron methyl 775propiconazole 90 example E calcium salt Example 6 Metsulfuron methyl 500MCPA 0 potassium salt Comparative Metsulfuron methyl 500 MCPA 0 exampleF potassium salt Example 7 Chlorsulfuron ammonium 660 Propiconazole 20salt Comparative Chlorsulfuron ammonium 660 Propiconazole 90 example Gsalt Example 8 Rimsulfuron sodium salt 700 2,4-D 0 ComparativeRimsulfuron sodium salt 700 2,4-D 60 example H Example 9 Trifluoxyfluroncalcium 1150 Propiconazole 0 salt Comparative Rimsulfuron calcium salt1150 Propiconazole 30 example I Example 10 Sulfometuron methyl 700 MCPA0 magnesium Comparative Sulfometuron methyl 700 MCPA 40 example Jmagnesium Example 11 Bensulfuron-methyl 660 2,4-D 0 ammonium saltComparative Bensulfuron-methyl 660 2,4-D 80 example K ammonium saltExample 12 Nicosulfuron calcium salt 720 Propiconazole 0 ComparativeNicosulfuron calcium salt 720 Propiconazole 60 example L Example 13Triflusulfuron-methyl 280 2,4-D 10 sodium salt ComparativeTriflusulfuron-methyl 280 2,4-D 60 example M sodium salt Example 14Chlorsulfuron ammonium 570 Propiconazole 0 salt ComparativeChlorsulfuron ammonium 570 Propiconazole 70 example N salt Example 15Ethametsulfuron-methyl 400 MCPA 10 sodium salt ComparativeEthametsulfuron-methyl 400 MCPA 60 example 0 sodium salt Example 16Azimsulfuron potassium 835 2,4-D 20 salt Comparative Azimsulfuronpotassium 835 2,4-D 90 example P salt Example 17 Chlorimuron-ethyl 430Propiconazole 0 calcium salt Comparative Chlorimuron-ethyl 430Propiconazole 80 example Q calcium salt Example 18 Flupyrsulfuron-methyl 380 Flutriafol 0 sodium salt Comparative Flupyrsulfuron-methyl 380Flutriafol 0 example R sodium salt Example 19 Flupyrsulfuron-methyl 190MCPA 0 calcium salt Comparative Flupyrsulfuron-methyl 190 MCPA 10example S calcium salt

Percent injury¹: injury to greenhouse sugarbeets after sprayed withfinal fresh water from the tank cleanout procedure.

The data summarized in Table I (using Protocol I) show that thecompositions of Example 1-19 according to embodiments of the presentinvention plus tank mix partner has a failure rate of 0. The comparativeexample A-S plus tank mix partner suffered a failure rate of about 79%.(Note: Test failure corresponds to a greenhouse result of >20% injury tosugarbeets in the bioassay test).

These results show that simple cleaning with fresh water afterapplication of the compositions according to embodiments of the presentinvention plus tank mix partner is successful without using additionalcleaning solution or ammonium hydroxide in the whole process ofcleaning. However the simple cleaning with fresh water after applicationof the corresponding sulfonylurea salt plus tank partner withoutEthanolamine is a failure without using additional cleaning solution orammonium hydroxide in the whole process of cleaning.

Tank Cleanout Protocol II (Sulfonylurea with No Tank Partner)

Step 1

Divide the Example 1-19 and Comparative example A-S to be tested into 2equal portions. Prepare a concentrated slurry with one portion, and apaste with the other portion. Spread and/or spray the paste and slurryonto the tank interior and let sit overnight. This procedure producesdried deposits on the tank surfaces to simulate worse-case fieldconditions.

Step 2

Rinse the tank interior with clean water, using a volume of 10-20% ofthe tank capacity, allowing the rinse to flush through the boom andhoses.

Step 3:

Fill the tank with clean water and agitate for 10 minutes. Discard thewater, flushing at least 10-20% through the boom and nozzles.

Step 4

Remove any nozzles, nozzle screens and in-line filters and clean withfresh water.

Step 5

Rinse the tank with clean water, using a volume of 10-20% of the tankcapacity. Allow the rinse water to accumulate in the tank and thendiscard through the boom and nozzles. Drain any remaining rinse waterfrom the tank.

Step 6

Fill the tank half full with water Sample water wash in tank (sampleused for bioassay test). Spray 10 to 20 gallons through the boom andthen sample at a nozzle (sample used for bioassay test). Drain theremainder of the contents.

Remark: In whole cleaning process, only fresh water was used. Additionalcleaning solution or ammonium hydroxide is not used.

TABLE II Initial Sulfonylurea concentrate in the tank Percent ExamplesSulfonylurea (ppm) injury ¹ Example 1 Thifensulfuon methyl 400 0potassium salt Comparative Thifensulfuon methyl 400 50 example Apotassium salt Example 2 Metsulfuron-methyl 500 0 sodium saltComparative Metsulfuron-methyl 500 60 example B sodium salt Example 3Pyrazosulfuron-ethyl 750 0 sodium salt Comparative Metsulfuron methyl750 10 example C sodium salt Example 4 Tribenuron methyl 600 0 sodiumsalt Comparative Tribenuron methyl 600 20 example D sodium salt Example5 Mesosulfuron methyl 775 0 calcium salt Comparative Tribenuron methyl775 85 example E calcium salt Example 6 Metsulfuron methyl 500 0potassium salt Comparative Metsulfuron methyl 500 20 example F potassiumsalt Example 7 Chlorsulfuron 660 10 ammonium salt ComparativeChlorsulfuron 660 70 example G ammonium salt Example 8 Rimsulfuron 700 0sodium salt Comparative Rimsulfuron 700 50 example H sodium salt Example9 Trifluoxyfluron 1150 0 calcium salt Comparative Rimsulfuron 1150 20example I calcium salt Example 10 Sulfometuron methyl 700 0 magnesiumComparative Sulfometuron 700 20 exampleJ methyl magnesium Example 11Bensulfuron-methyl 660 0 ammonium salt Comparative Bensulfuron-methyl660 50 example K ammonium salt Example 12 Nicosulfuron 720 0 calciumsalt Comparative Nicosulfuron 720 50 example L calcium salt Example 13Triflusulfuron-methyl 280 0 sodium salt ComparativeTriflusulfuron-methyl 280 70 example M sodium salt Example 14Chlorsulfuron 570 0 ammonium salt Comparative Chlorsulfuron 570 60example N ammonium salt Example 15 Ethametsulfuron- 400 10 methyl sodiumsalt Comparative Ethametsulfuron- 400 20 example O methyl sodium saltExample 16 Azimsulfuron 835 0 Potassium salt Comparative Azimsulfuron835 85 example P potassium salt Example 17 Chlorimuron-ethyl 430 0calcium salt Comparative Chlorimuron-ethyl 430 75 example Q calcium saltExample 18 Flupyrsulfuron- 380 0 methyl sodium salt ComparativeFlupyrsulfuron- 380 20 example R methyl sodium salt Example 19Flupyrsulfuron- 190 0 methyl calcium salt Comparative Flupyrsulfuron-190 50 example S methyl calcium salt

Percent injury¹: injury to greenhouse sugarbeets after sprayed withfinal fresh water from the tank cleanout procedure.

The data summarized in Table II (using Protocol II) show that thecompositions of Example 1-19 according to embodiments of the presentinvention in the absence of a tank partner has a failure rate of 0. Thecomparative example A-S in the absence of a tank mix partner suffered afailure rate of about 63%. (Note: Test failure corresponds to agreenhouse result of >20% injury to sugarbeets in the bioassay test).

The results show that simple cleaning with fresh water after applicationof the compositions according to embodiments of the present invention inthe absence of a tank mix partner is successful without using additionalcleaning solution or ammonium hydroxide in the whole process ofcleaning. However the simple cleaning with fresh water after applicationof the corresponding sulfonylurea salt in the absence of a tank mixpartner without Ethanolamine is a failure without using additionalcleaning solution or ammonium hydroxide in the whole process ofcleaning.

Bioassay Protocol

The bioassay protocol employed to determine the percent injury of thecrop (sugarbeets) sprayed with the final rinse solution after tankcleanout is described herein. Sugarbeet seedlings (at the two-leafstage) were grown in the greenhouse (14 hour photoperiod at 21° C. withlight and 10 hours at 17° C. in the dark) and sprayed with unmodifiedsamples of effluent from various sprayer cleanout procedures. Anautomatic belt sprayer was used, and the samples were applied at a rateof approximately 45 gal/A. Three replicate pots, with four sugarbeetplants/pot, were treated with each sample. The sprayer was rinsed 12times between each sample to ensure that there would not be carryoverbetween samples.

Plants were held in the greenhouse until they were evaluated, 14 to 23days after treatment. Injury of treated plants was assessed visually ona scale of 0 to 100 (0=injury, 100=complete kill) compared to controlplants. Injury ratings were based on the presence of various symptomsincluding reduced biomass, stunting, inhibited development, chlorosis,necrosis, leaf spotting, and leaf puckering or deformation.

The invention claimed is:
 1. A composition comprising by weight: (i) aherbicidal sulfonylurea water soluble salt, wherein the sulfonylurea isnicosulfuron; (ii) from 1% to 50% ethanolamine, wherein the compositionhaving ethanolamine improves spray equipment clean-out and reducesresidual sulfonylurea herbicide contamination left in the sprayequipment compared to the composition without the ethanolamine; (iii)optionally one or more additional formulating ingredients; a sum of allthe ingredients in the composition totaling 100%; and wherein a weightratio of the sulfonylurea water soluble salt to the ethanolamine is from1:90 to 90:1.
 2. The composition of claim 1 including from 2% to 90% ofthe herbicidal sulfonylurea water soluble salt.
 3. The composition ofclaim 1 including from 0% to 95% of the one or more additionalformulating ingredients.
 4. A method for reducing residual sulfonylureaherbicide contamination of a spray tank from which the sulfonylurea isapplied, comprising steps of: (a) formulating the sulfonylurea as anagriculturally suitable water soluble salt; (b) preparing a compositioncomprising by weight: (i) sulfonylurea water soluble salt, wherein thesulfonylurea is nicosulfuron; (ii) from 1% to 50% ethanolamine, whereinthe composition having ethanolamine improves spray equipment clean-outand reduces residual sulfonylurea herbicide contamination left in thespray equipment compared to the composition without the ethanolamine;(iii) optionally one or more additional formulating ingredients; a sumof all the ingredients in the composition totaling 100%; and wherein aweight ratio of the sulfonylurea water soluble salt to the ethanolamineis from 1:90 to 90:1; (c) applying the sulfonylurea salt composition toa crop while minimizing buildup of insoluble sulfonylurea in the spraytank, and (d) rinsing the spray tank substantially free of the residualsulfonylurea after application.
 5. The method of claim 4 including from2% to 90% of the herbicidal sulfonylurea water soluble salt.
 6. Themethod of claim 4 including from 0% to 95% of the one or more additionalformulating ingredients.
 7. The method of claim 4, wherein thesulfonylurea salt is used in the absence of a tank mix partner.
 8. Themethod of claim 4, wherein the sulfonylurea salt is used in incombination with a tank mix partner.